Abstract
For highly anisotropic layered material the influence of weak disorder due to randomly distributed impurities is studied in diagrammatic self-consistent approximation. It is shown that, in contrast to a quasi-one-dimensional case, extended states in an upper part of an energy band immediately appear if a weak interlayer tunnelling is switched on. Intensity of this tunnelling is characterised by the value of interplane exchange integral omega . The borderline energy between extended and localised states is equal to epsilon c=(h(cross)/ pi tau )ln( square root 2h(cross)/ omega tau ), where tau is the intralayer relaxation time. For epsilon F epsilon c it behaves as a metal. Here epsilon F is the Fermi energy. AC conductivity sigma ( omega ) is found for both cases. The localisation length is calculated for epsilon F<or= epsilon c.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call